100% usage CPU when kernel works

I have faced the following problem.
I have a kernel. But when I call it I receive 100% usage of the central processor.
Others host functions are not used.
Somebody knows what is the case of this problem? Is it normal?

See http://forums.nvidia.com/index.php?showtopic=28524 or the FAQ - fixed in 1.0

Suppose I have two videoadapters. Is it possible in to run CPU and GPU in parallel in sach case?